Adjustable cord lock



Sept. 6, 1938. J. NISENSON' 2,129,606

ADJUSTABLE CORD LOCK Fi1ed April 19, 1937 JUL/U5 /v/55/v50/v INVENTOR.

fl BY Jvmk ATTORNEY Patented Sept. 6, 1938 UNITED STATES PATENT OFFICE ADJUSTABLE com) LOCK Julius Nisenson, Brooklyn, N. Y. Application April '19, 1937,'S e'ria l No. 137,679 12 Claims. (outs-17) This invention relates generally toVenetian blinds and more particularly to an adjustable cord lock for use in conjunction with slat elevating or lowering cords as commonly used with said blinds.

The present invention to be hereinafter de-' scribed is suitable for use in conjunction with.

all types of Venetian blind head-bars or headpiece casings using similar cord arrangements for v 1 elevating and lowering the Venetian blind slats This invention is particularly suited for use in conjunction with a cord lock such as that vdescribed in Patent Number 2,036,231 granted to me April '7, 1936 to which reference may be had.

With this in view, only the principal features of i the invention are illustrated and described, as it will be understood by those skilled in the art that the same may be readily adapted to other I Venetian blind head-bars or head-piece casings.

20 Heretofore in Venetian blind head-bars or head-piece casings which are of uniform construction, and are manufactured as a unit having standard settings so that large scale production may be used to advantage, difiiculty has been 25"encountered with the cord locks thereon because diiferent sizes and numbers of slats have resulted in different weights with resultant differences in tension on the elevating and lowering cords.-

" Variation in tension changes the diameter of the "cords so that a fixed unadjustable setting for a light weight blind will allow a heavy weight blind to slip and conversely if the setting of the cord lock is unadjustably fixed in a position for use with a heavy blind, the cord lock will take 35 hold too easily and difficulty will be encountered in lowering the slats.

Among the objects of this invention is the provision of novel structure for the accurate and easy control of the cord lock or cord brake; which coacts with the cords for elevating or low-' ering the slats of a Venetian blind.

Another object herein is the provision of structure which is easily installed on the head-bar or head-piece casing and is readily adapted to h e ad bars or head-piece casings now in use.

A further object herein is the provision of an adjustable cord lock which is easily adjusted without the use of special tools after the Vene- 50 tian blind has been actually installed. The adjustment is thus -made under actual operating conditions, so that an accurate adjustment setting is obtained, and such setting is permanently maintained until readjustment is made.

A feature of the invention lies in the fact that since the adjustment thereof may be made without disturbing any other adjustments which may be part of the Venetian blind mechanism with 60. which this invention is included, adjustments may be readily made from time to time to allow for wear of the cords or other related elements.

' Another feature of this invention permits very fine adjustment of the cord brake or look so that a high degree of sensitivity is provided which is of specialvalue where the lateral movement of the cords'is restricted as will be more fully explained belofw.

A still further advantage of the present construction resides in the simplicity in manufacture and assembly with consequent economy.

These objects, further features, incidental ends and advantages will more fully appear in the progress of this disclosure and as pointed out in the appended claims.

In the accompanying drawing, similar reference characters designate corresponding parts throughout the several views in which:

Figure l is a fragmentary perspective view looking into ahead-piece casing at one end thereof, showing an embodiment of the invention.

Figure 2 is a partial vertical longitudinal sectional view of Figure 1 taken along the plane 22 thereon.

Figure 3 is .a partial perspective fragmentaryviewof the cord lock assembly frame with the dog, roller, and adjuster removed.

Figure 4 is a bottom plan view of Figure 3 with the cord separator removed.

Eigure 5 is a perspective view of the dog and pintle.

Numeral I0 indicates avenetian blind headpiece casing having a rearwardly bent front flange ,l I, a forwardly bent rear flange l2; a front wall i3; a rear wall M; a bottom wall l5; and a reinforcing tie-bar l6,

Manual control cords l1 and I8 pass upwardly through an opening (not shown) in the bottom wall l5, through an orifice 19 in the assembly frame indicated generally by numeral 20, over the roller2l and thence to any suitable slat elevating o-r' lowering means known in the art as will cause the cords to be under tension caused by the weightof the slats. Such means ordinarily include rollers, set at suitable points in the bottom wall 15, over which the cords pass totravel downwardly through orifices in said wall and to terminate in a weight bar adapted to raise the slats above it when thesame is raised. This construction is well known in the art and for this a "nalled in a pocket bearing formed by the two fice or guideway 3|. The inner end of the indentation 29 is provided with a widened portion 32.

An inner right angle plate 33 includes a vertical portion 34 and a pair of horizontal legs 35 and 36. Portion 34 is provided with orifices 31 and 38 and leg 35 is provided with an orifice 39. The inner and upper end of portion 34 is bent rearwardly at 40 in order to avoid abrading the cord IS.

The plate 33 is placed upon the plate 22in the manner illustrated in Figure 3 of the accompanying drawing and the legs 35 and 36 are affixed to the base 24 preferably by spot welding, thereby forming the frame 20. Orifices 25 and 31 and orifices 26 and 38 are thereby placed in alignment. A roller 2| is rotatably mounted between portion 23 and portion 34 on a pintle 4| which is journalled in the orifices 26 and 38. A dog 42 is rotatably mounted between portion 23 and portion 34 on a pintle 43 which is journalled in orifices 25 and 31. Pintles 4| and 43 are maintained in place in any suitable manner as by swaging the terminals thereof or by affixing said pintles to the roller and dog respectively.

The dog 421s provided with a working face 44 which is suitably scored or corrugated to provide an adequate gripping surface for engaging the cords I! and I8 which are disposed between said face and roller 2!. The circumferential movement of the dog is restricted in one direction by 1 contact with the cords IT and I8 and in the other direction by contact with an adjuster 45.

Adjuster 45 comprises a U shaped I plate including a leg 46 and a leg 41 and an upturned flanged portion 48. The flange portion serves to impart rigidity thereat. Leg 41 is provided with a threaded orifice 49 which is penetrated by a machine screw 50.

A cord separator 5| is composed of a substan-. tially right angle bent rod which is journalled at the outer end of the horizontal portion thereof in a pocket bearing formed by the two sides of indentation 28, the lower face of leg 36 and the upper face of bottom wall l5. The inner end of the horizontal portion of separator 5| is joursides of indentation 29, the lower face of leg 35 and the upper face of bottom wall l5. The vertical portion of separator 5| projects upwardly through the widened portion 32 of indentation 29 and the orifice 39, which are aligned. The separator is put in place when the assembly frame is placed within the casing l0. Frame 20 is maintained in position by a machine screw 52 which penetrates an orifice (not shown) in the bottom wall l5 and threadedly engages the orifice 3|] in base 24 and by the machine screw 5|] which penetrates an orifice (not shown) in the bottom wall l5, the guideway 3| and terminates in threaded engagement with the threaded orifice 49. An ordinary. lock-washer (not shown) is used on screw 59 between the head of said screw and the outer under surface of bottom wall l5.

Operation tendency of said screw to walk or shift in position as the same is tightened.

The proper operating position of dog 42 is determined by several factors, one of which is the weight of the slats and of the tilting tapes which are. supported by the elevating and lowering cords l1 and I8. Another factor is the relative elasticity of said cords. Under the tension of the weight of slats and tapes the cords stretch out and the diameter thereof is reduced as illustrated by the dot dash line 53 on Figure 2 of the accompanying drawing. When the cords l! and I8 are ina condition of reduced diameter it is necessary that the dog 42 lie closer thereto as illustrated in said figure by the dash-dash line 54 which is accomplished by moving the adjuster 45 inwardly or to the right as seen in Figure 2.

When proper adjustment of the adjuster 45 and the dog 42 has been made, in order to regulate the height of the blind slats the procedure is as follows: For raising the slats the exposed portion of the cords l1 and I8 is pulled downwardly and this in turn elevates the slats. During the elevation of the slats the dog 43 is relatively inactive and it is prevented from any wedging action. When the slats have been raised the desired amount, the cords are released and the weight of the slats pulls the vertical portion of the cords upwardly. The cords then frictionally engage the working face 44 causing the dog to turn upwardly and to wedge the cords between itself and the roller 2|, thus checking the descent of the slats. For lowering the slats, the exposed vertical portion of the cords l1 and 8 is given a short downward tug, this causes the dog 42' to move downwardly and to thereby stop the wedging action thereof. The cords are then allowed to move upwardly but at an angle as indicated by the dash-double-dot lines 55 on Figure 2, so that the cords do not engage the working face 44 sufficiently to actuate the dog 42.

It is possible by slightly changing the position of adjuster 45 outwardly or to the left as seen in Figure 2 to have the dog 42 wedge only when the cords are allowed to move upwardly at an angle to the left of the vertical, and to have the dog 43 clear said cords when they are allowed to move upwardly in a vertical position. Such arrangement is subject to two objections. One, that very often the particular Venetian blind installation, as for example a corner window, does not permit moving the exposed portion of the cords outwardly of the blinds to lock the dog. Two, that upon accidentally releasing the said cords the blind slats will fall whereas in the arrangement set forth above the descent of the slats will be automatically checked.

As may be readily understood the diameter of the cords may be reduced by wear, or by nonelastic stretching, but the adjuster 45 may be quickly and simply moved to compensate for any changes in operating condition.

The cord separator 5| operates to keep the cords I! and I8 apart so that they do not become twisted or tangled. Since the operating clearance between the dog 42 and the roller is set to accommodate only one cord, any tendency of one cord to ride upon or twist with the other would cause a jam, in turn requiring the casing ID to be demounted for correction. The separator, because of the widened portion 32 in indentation 29 and orifice 39, is capable of limited rotation about a horizontal axis longitudinally of easing Ill. This rotation coupled with the fact that the separator acts to keep the cords apart both below and to one side of the roller, assures troubleproof operation regardless of the direction or speed of travel of the cords.

It may thus be seen that I have provided a novel cord lock or brake adjuster and cord separator which is simple, economical, and effective in overcoming the disadvantages heretofore en-- countered.

The foregoing description has been made rather detailed for clearness of understanding only and no unnecessary limitations should be understood therefrom, but the appended claims should be construed as broadly as permissible in view of the prior art.

In the following claims the Word cord is intended to mean any cord, string, or rope-like element.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a Venetian blind having slats; a cord adapted to move said slats, gravity operated movable means to stop the travel of said cord initially actuated by the engagement of the cord therewith adapted in one position thereof to grip said cord, means to regulate the clearance between said movable means of said cord when the movable means is in the second position thereof including a horizontally shiftable plate adapted to engage said first means.

2. In a Venetian blind having slats: a. cord adapted to move said slats, a gravity operated movable dog mounted on a stationary pivot to check the travel of said cord initially actuated by the engagement of the cord therewith, adapted in the engaging position thereof to grip said cord and in the disengaging position thereof to clear said cord, means to regulate the clearance between said dog and said cord when the dog is in the disengaged position thereof.

3. In a Venetian blind having slats: a cord adapted to move said slats, a gravity operated pivotal dog initially actuated by the engagement of the cord therewith for checking the travel of said cord, adapted in the engaging position thereof to grip said cord and in the disengaging position thereof to clear said cord, means including a horizontally shiftable plate adapted to engage said dog to regulate the clearance between said dog and said cord when the dog is in the disengaged position thereof.

4. In a Venetian blind having slats, a cord adapted to move said slats, a stationary element over which the cord is adapted to travel, gravity operated movable means initially actuated by the engagement of the cord therewith, adapted in one position to stop the travel of said cord by compressing the cord between said movable means and said stationary element, and in a second position to clear and allow free travel to said cord, means to adjust the clearance between said movable means and said stationary element in the second position of the movable means.

5. In a Venetian blind having slats, a cord adapted to move said slats, a roller mounted on a stationary bearing over which said roller the cord is adapted to travel, gravity operated movable means initially actuated by the engagement of the cord therewith adapted in one position to stop the travel of said cord by compressing the cord between said movable means. and said roller, and in a second position to clear and allow free travel to said cord, means to adjust the clearance between said movable means and said roller in the second position of the movable means.

6. In a Venetian blind having slats: a head piece casing, a member stationary with relation to said casing, a cord adapted to move said slats, gravity operated movable means initially actuated by the movement of the cord therewith located within the'casing and adapted to stop the travel of said cord by compressing the cord against said stationary member, adjusting means within the casing to adjust the position of said first mentioned meanswith relation to said cord, means including a clamping screw accessible from outside the casing for moving said adjusting means, so that regulation of said adjusting means may be made without removing the head piece casing from a previously installed position.

'7. In a Venetian blind having slats, an element, cords adapted to move said slats and disposed laterally next to each other, said cords simultaneously approaching said element in one direction and leaving said element in another direction, separating means adjacent said element and adapted to maintain said cords apart in both said directionsof travel.

8. In a Venetian blind having slats, a. roller, cords adapted to move said slats and disposed laterally next to each other, said cords simultaneously approaching said roller in one direction and leaving said roller in another direction, separating means adjacent said roller and adapted to maintain said cords apart in both of said directions of travel.

9. In a Venetian blind having slats, an element, cords adapted to move said slats and disposed laterally next to each other, said cords simultaneously approaching said element in one direction and leaving said element in another direction, L shaped separating means adjacent said element and adapted to maintain said cords apart in both said directions of travel.

10. In a Venetian blind having slats, a roller, cords adapted to move said slats and disposed laterally next to each other, said cords simultaneously approaching said'roller in one direction and leaving said roller in another direction, L shaped separating means adjacent said roller and adapted to maintain said cords apart in both of said directions of travel.

11. In a Venetian blind having slats, an element, cords adapted to move said slats and disposed laterally next to each other, said cords simultaneously approaching said element in one direction and leaving said element in another direction, L shaped separating means adapted for limited rotation. about a substantially horizontal axis adjacent said element and adapted to maintain said cords apart in both said directions of travel.

12. In a Venetian. blind having slats, a roller, cords adapted to move said slats and disposed laterally next to each other, said cords simultaneously approaching said roller in one direction and leaving said roller in another direction, L shaped separating means adapted for limited rotation about a substantially horizontal axis adjacent said roller and adapted to maintain said cords apart in both of said directions of travel.

JULIUS .NISENSON. 

